Vacuum 2

We split into 2 teams. One did the floors and the other one laminated bulkheads.

Talking about what kind of work we have, how we can deal with it, how many people we need.

It looks simple to work on floors but it needs more hands so we decided to have 4 people on it, whereas 2 for bulkheads.

Pulling out the hose we used for blocking yesterday, we connected longer hoses to the manifold. Laminating yesterday was perfect, I didn't take a photo though.

Vac tape on before hand

We've got seperated vacuum bags for each floor so we vacuum them seperately using individual hose in them. Prior to do the same method yesterday, when one is ready to go we open it one by one.

Stack being ready. EDB and carbon uni need to be cut accurate as much as possible. Peel ply and the other stack doesn't really have to be perfect one instead we cut them half a length so that can be lapped over to work easy because of the shape on hull especially on the bow.

Vac tape in pleats on vacuum bag. Make the pleats reasonably enough to have good shrink. I was concerned about the shortage of its width. There wasn't a problem but I will cut it wider than I did.

The MDF for bulkheads has been coated three times and PVA spreaded on. The hose has another tube bored holes in it and we wrapped the wind break cloth up on it.

The collision bulkhead and glass for it being ready to be cut

Glass for another bulkhead cutting

a pressure gauge for the bulkheads laminating

on cutting perforated release film

Vac tape on MDF. This has a couple of holes on the edge, which part can't be used

just inside the tape diagonally

ready to go. Hull will be way more stiff after doing this job

The reason we used bleeder instead of wind break cloth is that it allows us to see the progress of resin migrating and it is cheaper.

It took less time to get ready to vacuum than yesterday. One advantage of vacuuming is that we can use less resin because the resin on the material can spread evenly further by vacuuming.

vacuum on

Upforward part of bow has been covered by fibreglass. We are going to give it a lap for 40mm on the centreline and right after the nosecone so that can be more stiff because we haven't got a stem.

Hose used for bulkheads laminating was put longitudinally following the edge with covered by bleeder. We have to make sure there is not a disconnection point of bleeder bridge to make vacuuming evenly.

They all connected with each other by bleeder.

Owing to the stiff shape on bottom of bow, we struggled to laminate fibreglass and the peel ply was even worse to make shape. It has to be better because we don't vacuum it.

cut where the big span on it

Talking about the girder laminating. I don't know what the sheet is made of.

1st coat which obviously is way cleaner than above. It has to be as flat as possible. We can check it by the reflection of lights.

Vacuum goes well. Checking the pressure gauge. If there is a leak, just give it a hand on it.

Organic fibre which is cheap and pretty strong and can be made in mold. I don't know the name...

dart/pleat
span
The reason why we bore holes on the foam when laminating is to get air out and to spread the resin well.

water-soluble
split
prepreg
pre-impregnated

indentation
NZ flex
organic fibre

Vacuum

We glued the last ring frame on EDB laminated yesterday, vacuumed the ring frame at stern and coved the other ones.

The laminating yesterday was well done checkin this morning. Peeling some peel ply off set the last ring frame up. We sanded around the ring frames to get rid of drops of glue, to make mechanical bonding and to get rid of lumps. Sand thoroughly but not too deeply especially on the glass and foam.

Extending glue sticks

The foam coudn't twist much to follow the shape at bow so that made a big gap on hinge point.

Chris added to coat of waxing on MDF for laminating.

We sliced a foam to make wedges to fill the gap mentioned above because it is not a good idea to fill the gap with only epoxy for many reasons. This is a temporary jig and we can see the table is slightly declined.

a huge gap

The wedge was a bit bigger than what it had to be so we cut some off with using bandsaw.

Mark a line, cut it.

nice filling

Measuring the length of the ringframes to cut carbon uni. What if we measured on the ring frames?

Chris demonstrated where the vac tape has to be put on. The line shown is sheer and the part above will be cut off. Carbon uni and EDB goes on right below the line, which is 50mm above the tip floors.

Stack sequence which helps us not to confuse, which has materials and sequence wrttien on it. Some simple sketches are on it as well.

cut the vacuum bag, put it on. It is rolled and folded in a width direction so it is quite big when being unfolded.

Put the vac tape on pleats.

Put some short hoses up on the manifold. Roll the vac tape around each mouth, push the hose into the mouth, done. These hoses are for blocking the leakage.

Fold like this picture, clamp them.

shut down switch(emergency?)

Vacuum pump. The tube on the left side is an oil pump for lubrication.

From left side, Auto/Manual switch, timer(when selecting Auto or Manual for keeping the vacuum until the power off), start/stop button, main power on/off switch.

This might be a pan of excess glue or something useless through the hose.

Cutting carbon uni with using straight edge on a nice and flat table or even on cardboard on it.

Minimise the offcuts by economical considering.

cut EDB for today as well

We use the longest one on the bottom. There are rings in green hose not to shrink the hose and the white one is narrow and thick enough to bare 1 ATM bar.

prewet ADR, mind the vac tape.

CU on

EDB goes on. 40mm on each side of ring frame is lap. We marked only one side and if the cutting is done well, it will be OK. The tip ringframe doesn't need the glass as much as the rest of its part needs so trim it off. Vac tape is already on.

take your time

peel ply, perforated release film(PRF), bleeder, vacuum bag which are cut in proper dimension. We used bleeder instead of wind break.

cover the peel ply on

on going

do the perforated release film

and bleeder which feels like cotton goes on it. One reason that we cover PRF on the peel ply is not to stick the peel ply and bleeder up. It helps glue to migrate evenly.

Put the vacuum bag on vac tape peeled the cover off.

Vacuum on. The resin gone through the holes of PRF to bleeder looks like spot which grows up.

We finished coving the ring frames we didn't do yesterday.

Final shot today

No pencil on aluminum, which contaminates it but ink or China something(like crayon) is alright for marking.

Waxing has to be done properly otherwise the vac tape stuck on the surface which is no no.

vacmobiles.com

stack sequence

One critical disadvantage of wind break is that it doesn't allow us to see how the resin migrates(progress)